The work of Broadbent and Lord [1]} presented two constructions of one-time uncloneable encryption. Their first construction, "conjugate encryption", which encrypts messages of length \(n = \lambda \) , is information-theoretic and \(\lambda \log _2(1 + 1/\sqrt{2})\) -uncloneable secure. This scheme upper-bounds the success probability of a cloning adversary by \(1/2 + 1/2\sqrt{2} \approx 0.85\)  in the single-bit message (\(n=1\) ) case.
